Dynamic absorber of washing machine

ABSTRACT

A washing machine having and using a dynamic absorber is disclosed. The washing machine includes a fixing member being provided at a bottom of an outer tub in the washing machine for storing wash water and an dynamic absorption member being extended from an outer surface of the fixing member, oscillating by vibration transmitted to the outer tub during rotation of an inner tub and having fixed mass and stiffness so as to absorb vibration of the outer tub. And, the dynamic absorption member includes a extension member extended from the outer surface of the fixing member to a radius direction and an mass member provided at outer end of the extension member.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of Korean Application No.P2002-0064331, filed on Oct. 21, 2002, which is hereby incorporated byreference as if fully set forth herein.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a washing machine, and moreparticularly, to a dynamic absorber for a washing machine absorbingvibration that occurs during a wash cycle.

[0004] 2. Discussion of the Related Art

[0005] In general, a washing machine is an apparatus removing variouscontaminants from clothes by using chemical emulsification of detergentand friction with wash water and mechanical impact of a pulsator to theclothes. Such a washing machine is classified into drum, pulsator, andagitator type.

[0006] In a drum washing machine, washing is performed by impact beinggenerated as laundries are raised and dropped by a rotation of a drum.And, in a pulsator and agitator washing machine, washing is performed byaction of detergent and impact being generated as laundries are raisedand dropped by a rotation of an agitator or pulsator coupled to a washshaft being vertically projected in the middle of the washing machine.In the aforementioned washing machines, washing is performed by impactbeing generated from a mechanical system.

[0007] Hereinafter, a general structure of the pulsator washing machineis explained in reference to drawings. As illustrated in FIG. 1, anouter tub 1 forming a case of a washing machine is provided in a cabinet(not illustrated) for storing wash water. Between the outer tub 1 andthe cabinet, a damper (not illustrated) is provided for supporting theouter tub 1 so as to absorb vibration generated during washing anddehydration.

[0008] An inner tub 2 is rotatably provided in the outer tub 1 and apulsator 3 is provided in the inner tub 2. A balancer 14 is provided formaintaining balance during a rotation of the inner tub at top of theinner tub and a driving motor 5 is provided for rotating the inner tuband the pulsator 3 at a bottom of the inner tub 2.

[0009] Explaining in more detail, a drive shaft 4 is coupled to thepulsator 3 and the driving motor 5 is connected to a bottom end of thedrive shaft 4. A bearing housing 8 is provided between the bottom end ofthe outer tub 1 and the driving motor 5. Bearing 6 and 7 are rotatablyprovided for supporting the drive shaft 4 at top and a bottom of thebearing housing 8. Accordingly, when the driving motor 5 is operated torotate the drive shaft 4 left and right, the pulsator 3 and the innertub 2 being coupled to the drive shaft 4 rotates each other andgenerates wash water current so as to wash laundries in the inner tub 2.

[0010] However, a conventional washing machine has problems as followed.First, as illustrated in FIG. 5, a vibration of the inner tub 2 is notincreased according to an increase in the number of rotation by anoperation of the inner tub 2 and the balancer provided at top of theinner tub 2. However, as a dotted line in FIG. 5, the outer tub 1 haslow stiffness and high flexibility, and the number of vibration iscontinuously increased by the increase in the number of the rotation ofthe inner tub 2. In the end, the vibration greatly reacts upon drivingmember such as the bearings 6 and 7, the bearing housing 8 and the driveshaft 4, and causes a damage of parts in an extreme case.

[0011] Second, although the damper is provided to absorb the vibrationin the conventional washing machine, the damper is only effective forreducing exceeded vibration in acceleration but not effective forabsorbing the vibration of the rated revolution. Therefore, there is alimitation in reducing dehydration time because high-speed dehydrationis not performed in the conventional washing machine.

SUMMARY OF THE INVENTION

[0012] Accordingly, the present invention is directed to a dynamicabsorber of washing machine that substantially obviates one or moreproblems due to limitations and disadvantages of the related art.

[0013] An object of the present invention is to provide a dynamicabsorber of washing machine that smoothly absorbs vibration at the outertub during high-speed dehydration.

[0014] Additional advantages, objects, and features of the inventionwill be set forth in part in the description which follows and in partwill become apparent to those having ordinary skill in the art uponexamination of the following or may be learned from practice of theinvention. The objectives and other advantages of the invention may berealized and attained by the structure particularly pointed out in thewritten description and claims hereof as well as the appended drawings.

[0015] To achieve these objects and other advantages and in accordancewith the purpose of the invention, as embodied and broadly describedherein, a dynamic absorber of a washing machine of the present inventionincludes a fixing member provided at a bottom of the outer tub and adynamic absorption member being extended from an outer surface of thefixing member, vibrating when the outer tub vibrates and therebyabsorbing the vibration of the outer tub. The dynamic absorption memberincludes an extension member extended from the outer surface of thefixing member in a radial direction; and a mass member provided aroundan outer circumference of the extension member.

[0016] The dynamic absorber of the washing machine further includes asupporting member being provided under the bottom of the outer tub andbeing coupled with the fixing member. The supporting member includes afixing groove formed on a bottom thereof for receiving a top of thefixing member. The fixing member is formed in a ring form.

[0017] The extension member includes a plurality of equally spaced barsbeing extended in a radial direction, and the extension member comprisesa round plate. A plurality of ribs is provided on a top surface of theextension member for supporting the extension member. The plurality ofribs has a first end connected to the outer surface of the fixing memberand a second end being connected to an inner surface of the additionalmass member. A bearing housing is provided at the bottom of the outertub and the fixing member is provided on an outer circumferentialsurface of the bearing housing.

[0018] In another aspect of the present invention, a washing machineincludes a cabinet, an outer tub provided in the cabinet for storingwash water, an inner tub rotatably provided in the outer tub forreceiving a load of clothes, a driving motor rotating the inner tub, adrive shaft having a first end coupled to the inner tub and a second endbeing coupled to the driving motor, a fixing member provided at thebottom of the outer tub, and a dynamic absorption member extended froman outer surface of the fixing member and vibrating when the outer tubvibrates and thereby absorbing the vibration of the outer tub.

[0019] The dynamic absorption member includes an extension memberextended from the outer surface of the fixing member in a radialdirection and a mass member provided at an outer end of the extensionmember.

[0020] A plurality of a bearing housing is provided for supporting thedrive shaft at the bottom of the outer tub and the fixing member isprovided on an outer circumferential surface of the bearing housing.

[0021] It is to be understood that both the foregoing generaldescription and the following detailed description of the presentinvention are exemplary and explanatory and are intended to providefurther explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings, which are included to provide afurther understanding of the invention and are incorporated in andconstitute a part of this application, illustrate embodiment(s) of theinvention and together with the description serve to explain theprinciple of the invention. In the drawings:

[0023]FIG. 1 illustrates a sectional view of an internal structure of aconventional washing machine;

[0024]FIG. 2 illustrates a sectional view of a washing machine having adynamic absorber according to the present invention;

[0025]FIG. 3A illustrates a bird-eye view of the dynamic absorberaccording to the present invention;

[0026]FIG. 3B illustrates a bird-eye view of another form of the dynamicabsorber according to the present invention;

[0027]FIG. 3C illustrates a bird-eye view of the other form of thedynamic absorber according to the present invention;

[0028]FIG. 4 illustrates a bird-eye view of the dynamic absorber havinga fixing member according to the present invention; and

[0029]FIG. 5 illustrates a graph compared vibration mode of the dynamicabsorber according to the present invention with a vibration mode of theconventional washing machine.

DETAILED DESCRIPTION OF THE INVENTION

[0030] Reference will now be made in detail to the preferred embodimentsof the present invention, examples of which are illustrated in theaccompanying drawings. Wherever possible, the same reference numberswill be used throughout the drawings to refer to the same or like parts.

[0031] As illustrated in FIG. 2, an outer tub 1 is provided for storingwater in a cabinet of a washing machine and an inner tub 2 is rotatablyprovided in the outer tub 1. The outer tub 1 is supported by a pluralityof dampers (not illustrated) connecting the cabinet of the washingmachine (not illustrated) to the outer tub in the washing machine.

[0032] A pulsator 3 is provided in the inner tub 2. The pulsator 3 iscoupled to top end of a drive shaft 4, and a driving motor rotating thedrive shaft 4 is coupled to a bottom end of the outer tub 1. A bearinghousing 8 having bearings 6 and 7 at top and bottom for rotatablysupporting the drive shaft 4 is provided between the bottom end of theouter tub 1 and the driving motor 5. A dynamic absorber 10 is providedfor absorbing vibration generated from the outer tub 1 on an outersurface of the bearing housing 8 when the inner tub 2 is rotated byrotation of the drive shaft 4.

[0033] The dynamic absorber 10 includes a fixing member 11 adhered tothe outer surface of the bearing housing 8 and a dynamic absorptionmember as illustrated in FIG. 3a. The dynamic absorption member includesan extension member and a mass member 13. An extension member in a roundplate form is extended from the outer circumferential surface of thefixing member 11 in a radial direction and vibrates, and the mass member13 is provided around an outer circumferential surface of the extensionmember 12. The mass member 13 vibrates with the extension member 12during vibration of the outer tub 1 and absorbs vibration of the outertub 1 at higher speed.

[0034] The fixing member 11 can be formed in various forms. For example,in case that the fixing member 11 is adhered to an outer circumferentialsurface of a cylindrical bearing housing 8, it is formed in a ring form.The extension member 12 includes a metal plate or a plastic round plate,the metal plate having a fixed stiffness and vibrating. Also, the massmember 13 can be formed in various forms for more effective vibrationabsorption.

[0035] There are number of ribs 12 a having a first end being connectedto the outer circumferential surface of the fixing member 11 and asecond end connected to the inner circumferential surface of the addedmass member 13 on a top surface of the extension member 12 asillustrated in FIG. 3B. The ribs 12 a support and complete the extensionmember during vibration of the extension member 12. The ribs 12 a isformed at a bottom surface of the extension member 12 or both a top andbottom surfaces of the extension member. Also, as illustrated in FIG.3c, the extension member 12 includes a plurality of equally spaced barsbeing extended in a radial direction.

[0036] Meanwhile, the structural elements of the dynamic absorber 10 canbe separately produced and assembled, or all can be formed as a singlebody. In this case, either the extension member 12 and the mass member13 or the fixing member 11 and the extension member 12 are formed as asingle body. Also, each element forming the dynamic absorber 10 can beattached to and detached from each other.

[0037] The stiffness and the mass of the extension member 12 and themass member 13 of the dynamic absorber 10 are tuned properly for a fixedvibration mode during dehydration. The tuning is set to the stiffness,volume of the outer tub 1 and the rated rotation during dehydration.

[0038] The following is an operation of dynamic absorber 10 with anaforementioned composition according to the present invention. Whendehydration of the washing machine is started, the drive shaft 4 rotatesby operation of the driving motor 5, and dehydration is performed byhigh-speed rotation of the pulstor 3 and the inner tub 2.

[0039] At this time, vibration is generated from the rotation of thedrive shaft 4 and the inner tub 2. This vibration is transmitted to thebearing housing 8. And, the extension member 12 and the mass member ofthe dynamic absorber 10 vibrate up and down so as to absorb vibration ofouter tub 1.

[0040] As illustrated in FIG. 4, the outer tub 1 includes a supportingmember 14 having an end surface being formed in form and having a fixinggroove 14 a on the bottom surface of the outer tub 1. The fixing member11 can be put in the fixing groove 14 a of the supporting member 14 andfixed by a screw (not illustrated). Ribs (not illustrated) for fixingcan be formed additionally to support the fixing member 11 at thesupporting member 14.

[0041] The form of the supporting member 14 is various and not limitedto a form being illustrated in FIG. 4. Instead of providing thesupporting member 14 separately, the fixing member can be fixed at abottom of the outer tub 1 by using a screw (not illustrated.) Thedynamic absorber can be adhered to an outside of a gear housing in whicha gear unit is provided in a washing machine including a clutch and agear unit in a driving device.

[0042] The effect of the present invention is followed. First, duringdehydration, relative vibration is generated from the inner tub 1according to high-speed rotation of the inner tub 2 and absorbed by thedynamic absorber 10. The vibration absorbency is more excellent comparedto that of the conventional washing machine. Second, low vibration andlow noise are realized during dehydration. Third, vibration beinggenerated from the relative vibration of the outer tub 1 and beingtransmitted to the driving member is reduced, and it protects parts soas to prolong life. Fourth, during dehydration, vibration from apredetermined number of rotations can be reduced by tuning the stiffnessand the mass of the dynamic absorber 10, and the number of ratedrotations can be set to a high number in order that the dehydration timeis reduced.

[0043] It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

What is claimed is:
 1. A dynamic absorber for a washing machine,comprising: a fixing member provided at a bottom of an outer tub; and adynamic absorption member being extended from an outer surface of thefixing member and vibrating when the outer tub vibrates and therebyabsorbing the vibration of the outer tub, the dynamic absorption membercomprising: an extension member extended from the outer surface of thefixing member in a radial direction; and a mass member provided aroundan outer circumference of the extension member.
 2. The dynamic absorberof the washing machine of claim 1, further comprising a supportingmember being provided under the bottom of the outer tub and beingcoupled with the fixing member.
 3. The dynamic absorber of the washingmachine of claim 2, wherein the supporting member comprises a fixinggroove formed on a bottom thereof for receiving a top of the fixingmember.
 4. The dynamic absorber of the washing machine of claim 1,wherein the fixing member is formed in a ring form.
 5. The dynamicabsorber of the washing machine of claim 1, wherein the extension memberfurther comprises a plurality of equally spaced bars being extended in aradial direction.
 6. The dynamic absorber of the washing machine ofclaim 1, wherein the extension member comprises a round plate.
 7. Thedynamic absorber of the washing machine of claim 6, further comprising aplurality of ribs provided on a top surface of the extension member forsupporting the extension member.
 8. The dynamic absorber of the washingmachine of claim 7, wherein each of the plurality of ribs has a firstend connected to the outer surface of the fixing member and a second endbeing connected to an inner surface of the additional mass member. 9.The dynamic absorber of the washing machine of claim 1, wherein abearing housing is provided at the bottom of the outer tub and thefixing member is provided on an outer circumferential surface of thebearing housing.
 10. A washing machine comprising: a cabinet; an outertub provided in the cabinet for storing wash water; an inner tubrotatably provided in the outer tub for receiving a load of clothes; adriving motor rotating the inner tub; a drive shaft having a first endcoupled to the inner tub and a second end being coupled to the drivingmotor; a fixing member provided at a bottom of the outer tub; and adynamic absorption member extended from an outer surface of the fixingmember and vibrating when the outer tub vibrates and thereby absorbingthe vibration of the outer tub, the dynamic absorption membercomprising: an extension member extended from the outer surface of thefixing member in a radial direction; and a mass member provided at anouter end of the extension member.
 11. The washing machine of claim 10,further comprising a supporting member being provided under the bottomof the outer tub and coupled with the fixing member.
 12. The washingmachine of claim 11, wherein the supporting member further comprises afixing groove receiving the top of the fixing member at a bottom of thesupporting member.
 13. The washing machine of claim 10, wherein thefixing member is formed in a ring form.
 14. The washing machine of claim10, wherein the extension member comprises a plurality of equally spacedbars being extended in a radial direction.
 15. The washing machine ofclaim 10, wherein the extension member comprises a round plate.
 16. Thewashing machine of claim 15, further comprising a plurality of ribsprovided on a top surface of the extension member for supporting theextension member.
 17. The washing machine of claim 16, wherein each ofthe plurality of ribs has a first end connected to the outer surface ofthe fixing member and a second end being connected to an inner surfaceof the mass member.
 18. The washing machine of claim 10, wherein abearing housing is provided for supporting the drive shaft at the bottomof the outer tub and the fixing member is provided on an outercircumferential surface of the bearing housing.